HIGH-SENSITIVITY AND DETECTIVITY RADIATION THERMOPILES MADE BY MULTILAYER TECHNOLOGY

A multi-layer technology for manufacturing thin-film radiation thermopiles is presented. The TS-72 thermopile made by this technology is characterized by a large sensitivity, S, a large relative detectivity, D*, and a small time constant, τ. For a sensor chip with 72 junctions under a sensitive area F = 0.2 mm2 and with a resistance R = 13 kΩ, we obtained at atmospheric pressure the values S = 180 V/W, D* = 5.5 × 108 cm Hz1/2/W and τ = 19 ms. When encapsulated in a krypton-filled TO-5 package at atmospheric pressure with a KRS-5 window (transmissivity T = 0.7), the sensor parameters are S = 290 V/W. D* = 8.8 × 108 cm Hz1/2/W and τ = 35 ms. © 1990.